/*
 * Copyright (C) 2012 The Guava Authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
 * in compliance with the License. You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software distributed under the License
 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
 * or implied. See the License for the specific language governing permissions and limitations under
 * the License.
 */

package com.google.common.io;

import static com.google.common.io.SourceSinkFactory.CharSinkFactory;

import com.google.common.base.Joiner;
import com.google.common.collect.ImmutableList;
import java.io.IOException;
import java.io.Writer;
import java.lang.reflect.Method;
import java.util.Map;
import junit.framework.TestSuite;

/**
 * A generator of {@code TestSuite} instances for testing {@code CharSink} implementations.
 * Generates tests of a all methods on a {@code CharSink} given various inputs written to it.
 *
 * @author Colin Decker
 */
@AndroidIncompatible // Android doesn't understand tests that lack default constructors.
public class CharSinkTester extends SourceSinkTester<CharSink, String, CharSinkFactory> {

    private static final ImmutableList<Method> testMethods = getTestMethods(CharSinkTester.class);

    static TestSuite tests(String name, CharSinkFactory factory) {
        TestSuite suite = new TestSuite(name);
        for (Map.Entry<String, String> entry : TEST_STRINGS.entrySet()) {
            String desc = entry.getKey();
            TestSuite stringSuite = suiteForString(name, factory, entry.getValue(), desc);
            suite.addTest(stringSuite);
        }
        return suite;
    }

    static TestSuite suiteForString(String name, CharSinkFactory factory, String string, String desc) {
        TestSuite stringSuite = new TestSuite(name + " [" + desc + "]");
        for (final Method method : testMethods) {
            stringSuite.addTest(new CharSinkTester(factory, string, name, desc, method));
        }
        return stringSuite;
    }

    private final ImmutableList<String> lines;
    private final ImmutableList<String> expectedLines;

    private CharSink sink;

    public CharSinkTester(CharSinkFactory factory, String string, String suiteName, String caseDesc, Method method) {
        super(factory, string, suiteName, caseDesc, method);
        this.lines = getLines(string);
        this.expectedLines = getLines(expected);
    }

    @Override
    protected void setUp() throws Exception {
        this.sink = factory.createSink();
    }

    public void testOpenStream() throws IOException {
        Writer writer = sink.openStream();
        try {
            writer.write(data);
        } finally {
            writer.close();
        }

        assertContainsExpectedString();
    }

    public void testOpenBufferedStream() throws IOException {
        Writer writer = sink.openBufferedStream();
        try {
            writer.write(data);
        } finally {
            writer.close();
        }

        assertContainsExpectedString();
    }

    public void testWrite() throws IOException {
        sink.write(data);

        assertContainsExpectedString();
    }

    public void testWriteLines_systemDefaultSeparator() throws IOException {
        String separator = System.getProperty("line.separator");
        sink.writeLines(lines);

        assertContainsExpectedLines(separator);
    }

    public void testWriteLines_specificSeparator() throws IOException {
        String separator = "\r\n";
        sink.writeLines(lines, separator);

        assertContainsExpectedLines(separator);
    }

    private void assertContainsExpectedString() throws IOException {
        assertEquals(expected, factory.getSinkContents());
    }

    private void assertContainsExpectedLines(String separator) throws IOException {
        String expected = expectedLines.isEmpty() ? "" : Joiner.on(separator).join(expectedLines);
        if (!lines.isEmpty()) {
            // if we wrote any lines in writeLines(), there will be a trailing newline
            expected += separator;
        }
        assertEquals(expected, factory.getSinkContents());
    }
}
